Valve stem



J. H. CLO` VALVE STEM July 16, 1935.

Filed July 5j 195o By Atorneys,

Patented July 16, 1935 UNITED STATES VALVE STEM JayHarry Clo, Baldwin, `N. Y., assignor` to A.

Schraders Son, Inc'., Brooklyn,

ration of New York N. Y., `a corpo- Application July s, 1930, seal 10.465306 5 claims. (ci. 285-122) The present invention` relates to valve stems for tire valves or the like, and more particularly toa novel construction Vof two-.piece valve stem and the manner of providing a leak-tight coupling 5 joint betweenthe parts of said two-piece valve stem. v l Heretofore pneumaticinnerftubes for tires have generally been provided with a one-piece .or integralkvalve stems, said stems being of different lengths and shapes, .depending upon the character of the wheel upon which the particular tire within which the inner tube was positioned, was to be mounted. In Yview of these variations in theleng'thsand shapes olvalve stems, dealers and service stations were obliged to carry a large numberof pneumatic tubes in stock to include these varioustypes of stems. f

It has been propo-sed to equip the inner tubes with ashort valve stem part of standard dimensions and to supply to the service station or dealer, valve stem extension elements tted withY the valve insides, said extension elements being keither straight or' bent so that when assembled with the valve stembase in the tube, any` desired .type of valve stem `couldbe provided. Although this proposal has not gone into extensive use, the valve stem parts attheir coupling ends have been provided with various forms of coupling meansfor `providing a leak-tight joint between the two valve stem parts, but for onereason or another said constructions have `been found deficientV or objecnon-aulak i y According to the present invention I providea novel construction for the valve stem parts at their coupling ends whereby an efficient and rigid leak-tight joint betweenthevalve stem parts is provided notwithstandingthe vconsiderable vibration to which such joints are subjected when`4 the tire is upona wheel in motion. A

According to Athe `present invention the valve :stem parts are of such character` that they may be quickly assembled without the aid of any special tools; `one wherein the coupling `joint therebetween provides av multiple seal againstpossible leakage, at least one of fsaid seals being `a` metal .toy metal joint'1 whichf is preferably ormedby metals having .different .degreesgof hardnessone of which will flow when forced into-contact with` the ,seating face on the-other, and wherein the assembly or the parts is such, that both'axial and torsional Yrigidity between the parts is accomplished and :in effect the equivalent of an integral valve construction is realized. The invention also embodies other advantages and `features of novelty which will be apparent irom ;the.detailed lline 6 6 of Fig. 1.

desc'riptionwhich follows, reference being had to the accompanying drawing; wherein;l Y

l Figurell `is a longitudinal section or aftwopiece valve stem, `said section" being taken along'rthe plane of; the line i--l of Fig. v l5 Fig. 2` isa view similar to'Fig. l showing a modi-` fication of the invention.

ofthe upper s'tem'part.` i

Fig. 4 is an elevation or" the stem base part or spu-d..V l

Fig. 5 is a section taken alongithe plane lof the line V5.--5 oaf Fig. 1. d Fig. 6 is asection taken alongr ,the plane of the Fig.`l 3v is an elevationA "or ftheloweriendv portion Fig. 7 is an axial section through the top" of the spud. A-

Fig. 8 is an elevation of a detail of the invention.

Fig.. 9 is a Alongitudinal section of a modified `form of the stern base part or spud..

Referring to `the drawing let A indicate a two- `piece tire valve stem consistingof -a stem `base part or spud B,.an upper valve stem part C and `a coupling `nut D foi" connecting the parts B and C together. Thebasep'art or spud B is provided with a conventional foot portion or flange b adapted yto engage against theV inner face of a .pneumatic tube, a tubular stem portion b. having a bore extending therethrough and provided. on its exterior surface with mutilated threads b3 and 3o opposite at surfaces b4 as is conventional on tire valve stems. The upper valve stem part Cmay `have any desired shape .and isadapted to lbe fitted atits outer end (not shown) with a conventional infiating valver or tirevalve inside..

According to the present invention the parts B and C are of novel construction and when assembledfinto cooperative relation through the medium of coupling nut'D, provide a simple, practicable1 and efficient valve stem, the joint between the parts; of which is both leak-tight and rigid under all conditions of use.. In a preferred ernbodiment of my invention, as shown'in Fig. l, the bore` throughfthe tubular stern portion b' isof different diameters; at its top it has a square 45 bore portion .b5 of large diameter, the corners of saidbore being chamiered, as shown at b6 in Fig. 5; below the square bore portion b5 the bore tapersV inwardly to` 'provide a packing seating Ishoulder b'l, `below which in turn `the bore bs is 50 of substantially uniform diameter, to a point slightly above the base flange b, whereat it is provided with a should-er b9. At its top the tubu* lar portion b is provided with `a plurality of axially extending slots b1, lwhich are cut tol pass 55 through the chamfered corners beto provide inv effect a plurality of clamping jaws. The slots b1D preferably eXtend down into the tapered Vshoulder bl, as shown in Fig. 7. Fitted within the bore b8 and seating against the shoulder b9 is a tubular plug bl which forms a leak-tight joint with the spud, the outer end of said plug being formed with a tapered surface blz. i The leak-'tight joint between the plug and the spud may be made in any preferred manner, for example, the plug may be driven or force-fitted into the spud, it may be soldered therein, or it may be made integral with the spud, as shown at b12a in Fig. 9. The spud is thus provided with a reentrantrnipple having'a tapered seating face in spaced relation to the wall of the bore through the spud. It is also proposed Y to maketherplug or nipple of harder metal than the upper stem part C, for aY purpose which will be presently made apparent.

The valve stem part C, which may be of straight or angular form, is formed Vat its coupling end withva-tubular extension" c, the lower end c of which is. of a diameter to freely pass into the bore b3. The tubular extension c above the end c is formed with an annular groove into which is disposed and preferably cured a rubber packing c2 Vhaving a tapered outer wall. Above the packing the extension is formed with a square shank c3, the corners of which are chamfered as shown at c4, the square shank portion tapering slightly inwardly toward the lower end and adapted to fit within the square recess b5. Above Ythe square shank portion the stem part C is formed with an annular rib c5 which is embraced by flanges d and'd formedron a bushing extension on the coupling nut D. j

, In the modification shown Vin Fig. 2 the upper end of the stem portion b is formed with an inwardly tapered thread 1931i and the' coupling nut D is provided with a oomplementally tapered, internal thread for Vcooperative engagement with the tapered thread 53a. To facilitate the spreading of the lower end c of the tubular extension c as it is forced over the tapered surface 1312 on the nipple, the wall of said extension supporting the packing c2 may be made relatively thin, as shown at e0. This construction will also augment the seating of the packing c2 against the wall of the bore ba. `To, still further facilitate the formation of a leak-tightseal between the lower end of the stem and the tapered surface within the spud, `I may-provide multiple Aseating contacts between 'said parts by forming the lower end of the entering member with spaced Vedges or ribs c", 'o8 adapted to engagethe tapered surface D12 and be deformed thereagainst.

Io couple the parts B and C together. the tubular extension c is inserted into the bore of the l spud which is carried by the tire inner tube. The

lowerend of the extension c will enter theY bore v rvb8 and abut against the taperedsurface 512 and the square shank c3 will enter the square recess b5, Upon threading the `coupling nut D. down over the threads b3 axial pressurewill be brought vto bear upon the end of the extension, which will be forced totridepover theY tapered surface 512, and in View of the relative softnessrof the eX- tension as compared with that of the nipple, the metal at the end of the extension will be caused to flow and provide'a leak-tight seal with the surface of the plug. It is proposed to so proportionthe parts that this flowing of the metal will continue ,until the outer surface of the end c will engage the wall of the bore bvand also form a seal therewith,as shown at D13.' In the course of the axial movement of the extension c the lower portion of the packing c2 will be forced into the bore 118 to provide a seal with the wall of said bore, and the upper portion ofsaidpacking will be forced into leak-tightV engagement with the taperedV seat b". Upon continuing the tightening of the coupling nut D after airtight seals have been provided between the lower Vend of the extension and the plug, the. lower end of the extension and the wall of the bore, and between the packing on the extension and the bore in the spud, a reactive force is set up between the threads on the spud and the threads on the nut, the horizontal component of which force acting radially inwardly upon the jaw-like ends of the stem portion b forces them into binding engagement with vthe square shank c3. According to theY modification shown inFig. 2 the tapered threaded connection between the top of the spud and the cou- Y pling nut will bring about the clamping action of the jaw-like ends of the stem portion b with theY square portion on thestem part C.

From'the foregoing description it will Abe ,apparent that there is provided a triple seal against leakage of air through the joint between the valve stem parts. There is also realized both torsional and axial rigidity between the members at said joint because ofthe clutch-like gripping of the jaws on the spud with the square shank of the upper stem part and the lockingengagement of the` lowerV end of the extension'c betvveenthe tapered nipple and the wall of the bore. V'Ihe equivalent of an integral one-piece valvestem is thus accomplished with all theV advantagesk of a two-piece stem.

In use, should the upper stem partrC become damaged or should a leak develop at the joint between stem parts, or should it be desired to use the inner tube on a wheel requiring a different form of upperL valve stem part, the upper stem part may be removed and replaced by another part,`it being remembered that the nipple in the spud is formed of harder metal than the upper stem part, and therefore the nipple seating face will withstand the spreading action of the lower end of the extension without any detrimental effect.

While I have shown and described certain preferred embodiments of my invention I do not wish to be limited to the details of construction dis-V closed, since modifications thereof may be re- Y sorted to.` without departing from the spirit of the invention; Y

What I claim is:

1. A device ofthe class described, comprising a tubular entered member having spaced seats within its bore,one of which is a reentrant ta- 2Q A device of the class fdescribed, comprisingV a tubular entered member, a tubular entering member, longitudinally spaced apart seating surfaces on each of said members adapted to cooperate with one another to providea multiple 'leak-tight seal between the members, at least one 0f said seals being provided by a metal to metal joint, and means for coupling the members together to eiect such seals.

3. A device of theV class described, comprising a tubular entered member, a tubular entering member, longitudinally spaced apart seating surfaces on each oi said members adapted to cooperate with one another to provide a multiple leak-tight sealV between the members, at least one of said seals being provided by a metal to metal joint wherea't a flowing of the metal at one of the seating faces takes place as the members are forced into coupling engagement.

4. A device of the class described, comprising a tubular entered member, a tubular entering member, means for providing a leak-tight seal therebetween, and cooperating means on said members adapted to hold them in coupled relation against relative axial, radialA and rotational movement, said last named means comprising complemental non-circular faces on the members, a coupling nut swivelly carried by one of the members, screw threads on the other member for engagement by the coupling nut, said threaded portion being longitudinally slotted to provide jaw-like portions adapted tov be moved inwardly when the coupling l nut is threaded home thereon.

5. A device of the class described, comprising a tubular entered member, a tubular entering member, means for providing a leak-tight seal therebetween, the entered member at its top having a bore of polygonal form longitudinally slotted at the angles of the bore to provide jaws, and the part of the entering member engaging within the top portion of the entered member being of vcomplemental polygonal form, and means for coupling said members together, said coupling means also functioning to move the jaws into clamping engagement with the entering member.

J. HARRY OLO. 

